1. H23A14 Briton Ferry Gas Works Land Contamination Antreas Christodoulides Georgios Efstathiou Antreas Christodoulides Georgios Efstathiou

2. H23A14 Brief History Briton Ferry, Neath Port Talbot, Wales. Gasworks operated on the site from the late 1890s until the 1970s. South part sold in 1930 for residential development. Until 1976 the north part was used for gas storage and distribution. North part also sold for house development in 1976.

3. H23A14 Map

4. H23A14 Contamination Contaminants arise from coal gas manufacture, gas purification and the handling of by-products. This includes:  Heavy metals  Cyanides  Phenols  Petroleum hydrocarbons  Tars

5. H23A14 Investigation Introduction in 2001 of legislation under the Environmental Protection Act 1990. Investigation of any suspicious contaminated areas. In 2005 investigations commenced by JACOBS consultant company. Tap water testing. Surface Soil sampling (Gardens). Deeper soil sampling. Ground water sampling.

6. H23A14 Investigation Findings No significant pollution of tap water. Some evidence of surface contamination. Like Tarry materials, Polyaromatic Hydrocarbons, large concentrations of Cyanides. Deep soil and groundwater included contaminants like ammonia, metals, petroleum hydrocarbons, BTEX, phenols and other organic compounds.

7. H23A14 Affected Areas Area 1: -Former location of purifier plant -Raised cyanide levels Area 2: -R etort house and gas holders -Volatile petroleum hydrocarbons PAHs Area 3: - Tar wells and tar tanks -Deep ground and groundwater contamination

8. H23A14 Remediation Strategy Removal and disposal of contaminated soils. Installation of a Geotextile membrane, to avoid contact with contaminated soil. Backfill with clean imported material. Deeper soil removal at former tar tank locations. Long term monitoring of groundwater through boreholes.

9. H23A14 Alternatives Cement Stabilization/Solidification Similar technique like Geotextile Membrane. Uses cement as a solidifier. Prevents contact of contaminated soil with clean soil. Prevents water pollutants from moving. Clay soil Impermeable

10. H23A14 Any Questions